A multilevel systems approach for effective public health actions

Abstract

The complex and multilevel nature of health has made it challenging to evaluate public health actions. Performing comparative analyses in different contexts is particularly challenging. Health care associated infections are a public health threat in need of more effective hospital infection control. They are associated with significant morbidity and mortality worldwide and place a large burden on health care resources. Hospital infection control has had mixed success, with many aspects of context playing a large role. As such, systems approaches are called for that improve the capability to capture multilevel determinants, context and complex and causal interrelationships (such as feedback and nonlinearity) that may change over time.In this thesis a novel ‘multilevel systems approach’ is proposed that appears capable of complex, multilevel and causal analysis. The approach draws together qualitative and quantitative concepts and methods from four multilevel systems theories and methodologies: the Realist approach, Systems Thinking, Health System Frameworks and System Modelling and Simulation. The power and feasibility of the approach to analyse and evaluate complex public health actions in different contexts is examined by its specific application to hospital infection control. In particular, to the control of Methicillin-resistant Staphylococcus aureus (MRSA), a health care associated multidrug-resistant infection.In doing so, the context-specific (and nonlinear) effects of competing hospital infection control policies on changing trends in the incidence rate and prevalence of MRSA were measured and compared. The capability to evaluate multiple infection control policies implemented in different and interacting ward settings simultaneously, had not previously been demonstrated. This subsequently provided valuable insights. Given the contribution and generalisability of the multilevel systems approach, its application toward a range of public health actions is recommended